Most home blood pressure monitors let you switch from kPa to mmHg through a settings menu or a button combination you can access in under a minute. The exact steps vary by brand and model, but the process almost always involves holding down a specific button while the device is off, then powering it on, or navigating a small on-screen menu. If your monitor is showing readings like 16.0/10.7 instead of the familiar 120/80, it has simply been set to kilopascals, and the fix is straightforward.
Why Your Monitor Might Be Displaying kPa
Blood pressure has been measured in millimeters of mercury (mmHg) since the earliest sphygmomanometers used an actual column of mercury to register pressure. That convention stuck in most of the world’s clinics, hospitals, and home-health settings. But kilopascals are the official SI (metric) unit of pressure, and some countries and regulatory bodies have pushed to adopt kPa for blood pressure readings. Because manufacturers sell the same devices globally, many monitors ship with the ability to display either unit. A stray button press during setup, a factory default aimed at a different market, or a device reset can leave your screen showing kPa when you expected mmHg.
The debate over which unit clinicians should use has lingered for decades. A correspondence published in The Lancet noted that doctors feel comfortable with the conventional mmHg, yet that measurement is just as abstract to a patient newly diagnosed with high blood pressure as kPa is to most doctors.1The Lancet. Blood pressure measurement: should we continue to use mm Hg or switch to kPa? In practice, though, mmHg remains dominant. Clinical guidelines worldwide define hypertension thresholds in mmHg (for example, 130/80 or 140/90), your doctor records your readings in mmHg, and virtually every published blood pressure study reports values in mmHg. So if your device is speaking kPa, you almost certainly want to switch it.
General Steps to Change the Unit on Most Monitors
While every brand has its own quirks, the process follows a common pattern across the vast majority of automatic oscillometric monitors sold for home use. Here is the general approach:
- Turn the device off. Make sure the monitor is fully powered down, not just idle or in standby.
- Press and hold a button. On many models, you hold down the START/STOP button, the SET button, or a dedicated memory/clock button. Some monitors use a combination of two buttons pressed simultaneously.
- Power on while holding. With the button still depressed, turn the unit on (or it may power on automatically after a few seconds of holding). The display will typically enter a settings or configuration mode rather than starting a measurement.
- Toggle the unit. Once you see “kPa” or “mmHg” flashing on the screen, press the same button (or a different one, depending on the model) to toggle between units. Select mmHg.
- Confirm and exit. Press START or simply wait a few seconds. The monitor saves the selection and returns to its normal measurement mode.
If your monitor has a digital menu with arrow keys or a touchscreen, the unit option is usually buried under a “Settings” or “Device” submenu, sometimes labeled with a wrench or gear icon. Look for a line reading “Unit” or “Pressure Unit” and change it there.
Brand-Specific Guidance
Because the button sequence varies, here are pointers for some of the most widely used home blood pressure monitor brands. These cover the most common models, but if your exact model differs, check the user manual (most manufacturers post PDF manuals on their websites for free).
Omron
Omron is one of the most popular home monitor brands worldwide, and their devices are frequently used in research settings as well.2PubMed Central. Noninvasive Blood Pressure Monitoring via a Flexible and Wearable Piezoresistive Sensor On many Omron upper-arm models (such as the HEM-7120, HEM-7130, and M-series models), you turn the device off, press and hold the START/STOP button for several seconds until the display enters a settings mode, then press the button again to toggle from kPa to mmHg. Some newer Omron models with Bluetooth connectivity let you change units in the companion smartphone app instead. On wrist models, the process is similar but may involve the SET or clock button.
Braun
Braun ExactFit and similar models typically use the memory or “M” button. With the device off, hold the M button, then press the power/start button. When the unit display blinks, press M to toggle. Release and let the device save.
Beurer
Many Beurer monitors have a dedicated SET button on the side or bottom. Turn off the device, press and hold SET, then power on. The screen enters settings mode, and you cycle through options (time, date, unit) using the SET or arrow buttons until you reach the pressure unit, then toggle to mmHg.
Withings (Nokia Health)
Withings BPM Connect and BPM Core are managed almost entirely through the Withings Health Mate app. Open the app, go to the device’s settings page, and change the unit there. The monitor itself has minimal physical controls.
Other Brands
For less common brands, the manual is your best resource. If you have lost the paper copy, search the manufacturer’s website or type the model number followed by “user manual PDF” into a search engine. The unit-change procedure is almost always in the first few pages of the setup section.
Converting kPa to mmHg Manually
If you cannot change the setting for some reason, perhaps the button is unresponsive, or you are using a hospital-grade monitor that is locked to kPa by institutional policy, you can convert any reading yourself. The math is simple: multiply the kPa value by 7.5 (more precisely, 7.50062, but 7.5 is close enough for clinical purposes). Going the other direction, multiply mmHg by 0.133 to get kPa.
A few common reference points make this easy to sanity-check:
- 120/80 mmHg (textbook normal) = roughly 16.0/10.7 kPa
- 140/90 mmHg (a common hypertension threshold) = roughly 18.7/12.0 kPa
- 90/60 mmHg (low end of normal) = roughly 12.0/8.0 kPa
- 180/120 mmHg (hypertensive crisis territory) = roughly 24.0/16.0 kPa
If your reading in kPa is, say, 17.3/11.2, multiply each number by 7.5 to get approximately 130/84 mmHg. That is easy enough to do on a phone calculator or even in your head once you get used to it. But because there is always a risk of arithmetic mistakes when you are tracking something as important as blood pressure, switching the device itself is the better long-term solution.
Why mmHg Still Dominates Clinical Practice
You might wonder why medicine clings to a unit named after a toxic liquid metal that most modern devices no longer use. The answer is largely institutional momentum, but that momentum is strong. Every major hypertension guideline, from the American Heart Association to the European Society of Hypertension, defines diagnostic cutoffs in mmHg. Prescription decisions, emergency protocols, and anesthesia management all revolve around mmHg thresholds that clinicians have memorized and internalized over years of training. Switching the entire medical world to kPa would require rewriting guidelines, retraining practitioners, and re-calibrating the clinical intuition that lets a nurse glance at “88/50” and immediately know the patient is in trouble.
Some countries, particularly in parts of Europe, have tried to nudge clinical practice toward kPa. But even in those settings, mmHg remains the lingua franca for blood pressure communication in most hospitals. The practical implication for you: when you share readings with your doctor, pharmacist, or telehealth platform, use mmHg. If a reading is in kPa, convert it first to avoid confusion.
Accuracy Matters More Than Units
Changing the display unit does not affect the accuracy of your monitor. The sensor inside a home blood pressure device measures pressure in its own internal units and then converts to whatever the screen is set to display. Toggling from kPa to mmHg does not recalibrate the device, introduce rounding errors, or degrade the measurement in any way. The underlying pressure value is identical.
What does affect accuracy is whether the monitor has been validated against accepted standards. Clinical validation protocols compare a device’s readings to a reference standard across a range of blood pressure values. Research routinely uses simulators that generate specific systolic and diastolic pressures, typically spanning from hypotensive ranges around 90/50 mmHg up to severely hypertensive values of 220/180 mmHg, to test whether a monitor reads correctly across the full spectrum.2PubMed Central. Noninvasive Blood Pressure Monitoring via a Flexible and Wearable Piezoresistive Sensor If your device has passed such validation (look for mentions of ISO 81060-2 or ESH protocol on the box or manual), you can trust its numbers regardless of which unit is displayed.
One thing worth noting: home monitors use an oscillometric method, which estimates blood pressure from pressure oscillations in the cuff rather than listening for sounds the way a manual measurement does. That estimation process is generally reliable for most people, but it can be less accurate in certain situations. In critically ill patients with very low blood pressure, for instance, noninvasive cuff readings have been shown to correlate statistically with invasive arterial measurements yet still fall short of clinical agreement thresholds set by the European Society of Hypertension.3PubMed. Comparison of noninvasive blood pressure monitoring with invasive arterial pressure monitoring in medical ICU patients with septic shock For everyday home monitoring of someone who is not in an ICU, though, a validated oscillometric device is perfectly appropriate.
What About Mean Arterial Pressure
Some monitors display a third number alongside systolic and diastolic values: mean arterial pressure, or MAP. This is an estimate of the average pressure in your arteries during one cardiac cycle. Most consumer monitors do not show it, but if yours does, the same unit toggle applies. MAP will switch between kPa and mmHg along with the other readings.
If your device shows systolic and diastolic but not MAP and you need it for some reason, you can estimate it with a simple formula: take one-third of the systolic value and add two-thirds of the diastolic value.4Biomedical Engineering Advances. Oscillometric Waveform Evaluation for Blood Pressure Devices For a reading of 120/80 mmHg, that works out to about 93 mmHg. Clinicians use MAP mainly in hospital settings to assess organ perfusion, so most home users will never need it, but it is worth knowing the number exists if your monitor shows it and you are wondering what it means.
Troubleshooting When the Setting Will Not Change
Occasionally, people report that the button sequence does not seem to work. A few common culprits:
- Low batteries: Some monitors will not enter settings mode when battery power is critically low. Replace the batteries or plug in the AC adapter and try again.
- Cuff still connected and inflated: If the cuff retained air from a previous reading, the device may think a measurement is in progress. Disconnect the cuff tube, let any residual air escape, reconnect, and try the button sequence again.
- Wrong button or timing: The hold duration matters. Some models require you to hold a button for three seconds, others for five or more. If you release too early, you just turn the device on normally instead of entering settings mode. Try holding longer.
- Locked by app or institutional setting: Connected monitors managed by a hospital or telehealth service may have their settings locked remotely. Contact the provider or check the companion app for a lock or admin setting.
If none of this works and you have verified you are following the correct procedure for your specific model, the device may have a hardware fault. Contact the manufacturer’s support line. Most reputable brands offer a warranty that covers settings-related malfunctions.
Recording and Sharing Your Readings
Once your monitor is showing mmHg, keep a simple log. Write down the systolic number, the diastolic number, and the date and time. Many doctors prefer morning readings taken before medication and before eating, plus an evening reading. Two or three consecutive readings a minute apart, with the first one discarded, give a more reliable picture than a single measurement.
If you use a connected monitor that syncs to a phone app, double-check that the app is also set to mmHg. Some apps have their own independent unit setting that can override or conflict with the device’s display. When you bring your log to a medical appointment or upload it to a patient portal, mmHg ensures your doctor can interpret the numbers at a glance without mental arithmetic. The whole point of home monitoring is to give your care team data they can act on quickly, and using the same unit they think in makes that seamless.
For people tracking blood pressure over weeks or months, consistency in conditions matters far more than the unit displayed. Measure at the same times each day, sit quietly for five minutes beforehand, keep your feet flat on the floor, and use the correct cuff size. A perfectly converted kPa reading taken while you are rushing out the door tells your doctor less than a properly taken mmHg reading recorded under calm, standardized conditions.
When kPa Might Actually Be Preferred
There are a handful of situations where keeping your monitor on kPa makes sense. If you live in a country where your healthcare provider records and discusses blood pressure in kPa, switching to mmHg could introduce the same communication gap you are trying to avoid, just in reverse. Some Scandinavian and Central European clinics historically used kPa, and a few still do. If your doctor hands you a target of 18.0/11.3 or lower, keeping your home monitor in kPa avoids the need to convert every time you compare your reading to the goal.
Scientists working in physiology or biomedical engineering may also prefer kPa because it integrates cleanly with other SI units used in fluid dynamics and material science. If you are a researcher calibrating a pressure sensor or running a simulation, kPa is the natural unit and mmHg would be the odd one out. For the average person tracking their health at home, though, mmHg is almost always the right choice, simply because it is what everyone around you, from your pharmacist to your cardiologist, speaks fluently.